Add Sinon to Cypress TypeScript interface

[bahmutov]

Cypress v4.1.0

Cypress.sinon is missing from TypeScript definition

[cypress-bot]

The code for this is done in cypress-io/cypress#6725, but has yet to be released.
We'll update this issue and reference the changelog when it's released.

[cypress-bot]

Released in 4.2.0.

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